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(No Model.) 2 Sheets-Sheet 1. I

G. W. STAFFORD. SHEDDING MECHANISM FOR L-OOMS.

No. 475,625. Patented May 24, 1892.

(No Model.) 2 SheetsSheet 2.

G. W. STAFFORD. SHEDDING MECHANISM FOR LOOMS.

No. 475,625. Patented May 24, 1892.

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UNITED STATES PATENT OFFICE.

GEORGE W. STAFFORD, OF PROVIDENCE, RHODE ISLAND.

-SHEDD|NG MECHANISM FOR LOOMS.

SPECIFICATION forming part of Letters Patent No. 475,625, dated May 24,1892.

Application filed November 16, 1891- Serial No. 412,083. (No model.)

To all whom it may concern.-

Be it known that I, GEORGE W. STAFFORD, a citizen of the United States,residing at Providence, in the county of Providence and State of RhodeIsland, have invented certain new and useful Improvements in SheddingMechanism for Looms, of which the following is a specification,reference beinghad therein to the accompanying drawings.

My invention relates to double-action dobbies or shedding mechanisms forlooms. These have heretofore generally comprised a connector orjack-lever which is pivotally mounted at mid-length thereof upon eachharness-operating lever, hooked jacks which are pivoted to the upper andlower ends, respectively, of each connector or jack-lever, and arecontrolled in their position by means of patternindicators applied tothe surface of a patterndrum or to a chain which passes around asuitable cylinder or drum, the said indicators acting to determine theposition of the jacks through intermediately-placed pattern or indicatorlevers, and wires or needles resting upon the said pattern or indicatorlevers and supporting the free ends of the hooked jacks. Usually thelower jack of the pair of jacks which are pivoted to the opposite endsof a connector or jack-lever rests upon the upturned inner end of onepattern or indicator lever, while the upper jack of the said pair issupported by a vertical wire or needle which at its lower end rests uponthe inner end of an adjacent pattern or indicator lever. The hookedjacks, when permitted to descend by the pattern-controlling devicesaforesaid, are engaged by reciprocating draw-bars, which are calledlifters. One lifter is placed beneath the upper series of hooked jacksin the dobby or shedding mechanism in position to engage therewith whenrequired, and the other lifter is placed beneath the lower series ofhooked jacks in position to engage therewith when required. The liftersare reciprocated in parallel horizontal planes, and they move in a givendirection alternately, they being actuated by devices connected with thedriving mechanism of the loom,whereby one of them is moved outward priorto one pick of the loom and the other is moved outward prior to the nextpick of the loom, and so on successively.

The object of my invention is to provide a double-action dobby ofimproved and simplified construction and at the same time to provide adobby that shall retain all of the advantages that are found to bepossessed by known dobbies of this class.

My invention consists of certain novel and improved combinations andarrangements of parts, which will now be described with reference to theaccompanying drawings, and which will be particular pointedout anddefined in the claims at the close of this specification.

Figure 1 of the drawings is a view in side elevation of a dobbyembodying my present i11- vention. Fig. 2 is a-view of the said dobby inend elevation, the same being viewed from the right-hand side in Fig. 1,the upper portions of the harness-levers being broken away in the saidFig. 2 and thehooked jacks or hooks and certain adjacent parts beingomitted. Fig. 3 is a view showing the dobby as it would appear inlongitudinal section, parts of the side frame being broken away. Fig. eis a View in plan of the side frames and certain parts, which willhereinafter be referred to. Fig. 5 is a detail view showing a section online 00 0c in Fig. 3.

In the drawings, a a are the side frames of the dobby, and b is a rod orshaft fixed in downwardly-projecting extensions of the said side frames,this shaft serving as the pivotal support or fulcrum for theharness-operating levers c. The upper ends of the levers project upthrough and are guided in the slots of an over arching curved grate d,which is fastened by bolts e to the side frames or a. When in theirinnermost position, the inner edges of the said upper ends of theharness-levers 0 rest against the outer face of a back-stop bar f, whichis secured by bolts 9 to the said side frames a a.

Each harness-lever c has on one side thereof two headed studs h h, thestud 72' being nearer the center or fulcrum on which the harness-levers0 turn than the stud h, the head of this stud h being removed in Fig. 3in order to show the mannerin which the hooked jacks or hooks z' z" arefitted to the stems of the studs h h. The jacks or hooks c e" haveslotted or looped body portions, as shown in Fig. 3, which fit upon thestuds, their outer ends 71 being hooked. The outer portion of the bodyof each jack or book is expanded or increased in vertical width at 41this expanded or widened portion being connected by an incline t withthe narrower portion of the jack or hook, and the object of this featureof oonthe lifters or draw-bars 0 0, are determined by the indicators Z,which are applied to bars 1, passing around a grooved drum on cylinderP, the indicators acting against the under side of the outer ends of thepattern or indicator levers m m, which are mounted side by side upon across-rod m supported in the side frames at a. The inner end of thepattern or indicator lever m supports a vertical wire or needle it, uponthe upper end of which rests the upper jack '1', while the lower jack 2"rests directly upon the inner end of the patternlever m. The jacks, whentheir hooked ends are permitted to remain in their depressed position,as in the case of the jack '5 in Fig. 3, are engaged by lifters ordraw-bars 0 0' and moved outward thereby. These lifters or draw-barshave connected therewith jack-returning bars 11 p, which serve,respectively, asv a lifter or draw-bar moves inwardly to force inwardly,also, any jack or book which may have been carried outward by thecorresponding lifter or draw-bar in the outward movement thereof andwhich may not have been returned to the normal position (represented inFig. 3) in consequence of the movement of a harness-lever inward.

The ends of the lifters or draw-bars and connected returning-barsslidein slots a 0, formed in the side frames a a. Each end of eachlifter or draw-bar is pivotally connected with one end of aconnectingrod q. The other ends of the rods q pertaining to the upperlifter or draw-bar are connected to upwardlyextending arms 0* onopposite ends of a rockshaft .9, which is journaled in bearings in theside frames. a a, and the other ends of the rods q pertaining to thelower lifter or draw-' bar are connected to downwardly-extending l arms1" on the said shaft s. The shaft 8 is provided at one end with an arm.9, which in practiceis connected by a rod to some suitable moving partof the loom, to which the dobby is applied, the said rock-shafts beingin practice operated with such relative timing as that one lifter ordraw-bar shall be caused to move outwardly at one pick of the loom andthe other lifter or draw-bar shall be caused to move outwardly at thenext pick of the loom, and so on successively.

For the purpose of impartinga step-by-step l movement of rotation to thedrum orcylinder Z the shaft 1 of the said drum or cylinder is providedwith a ratchet-wheel t, the teeth of which are engaged by a pawl u,pivoted to one of the arms 1*. The drum or cylinder is prevented fromoverrunning by means of a cheek-wheel 1), which is fast to the shaft Zin succession by the curved end of the holding-arm w, the said arm beingpivoted to the side frame a and acted upon by a spring w. With theobject in view of imparting more movement progressively to the rearharnesslevers in the loom I communicatemore movement to the rear ends ofthe lifters or drawbars than to the forward ends thereof. I effect thisby connecting the rods q to the arms 0' r on one side of the dobby atpoints which are proportionately farther from the axis of the shaft 8than arethe points at which the rods g on the other side of the dobbyare connected with the corresponding arms '1' r at that side. For thepurpose of avoiding lost motion when the harness-levers and lifters ordraw-bars are thus operated the back-stop bar f is secured to the sideframes a a in an inclined position, which is parallel with the iposition occupied by the lifters or draw-bars 1 when in their innermostposition. In order to prevent the hooks or jacks from moving too farinward and so insuring that they shall be indicated when required, across-wire i is passed through the open portions of the hooks I or jacksof each series, these wires being mounted in lugs projecting from theends of the grates 7c. These cross-wires i extend from one side frame tothe other in an inclined or angular position, as indicated in Fig. 5,they being parallel with the outer face of the back-stop barf. Inasmuchas the jacks t" engage with the studs h, which, are located nearer thecenter A or fulcrum on which the harness-levers turn *than are the studs71, with, which the jacks i engage, it is necessary to provide formoving the upper lifter or draw-bar through a greater *path of movementthan that through which I the lower lifter or draw-bar is moved. Itherefore connect the rods q pertaining to the said upper lifter ordraw-bar to the arms 'rat l points which are proportionately fartherfrom the axis of the shaft 3 than are the points at j which the rodsqpertaining to thelower lifter 4 or draw-bar are connected to the arms'1".

The grates k 10 preferably are cast in one land from the front side ofthe casting pro- ;jects a series of lugs 10*, the spaces between theselugs forming pockets for the reception of the upper ends of the needlesn, the latter being retained in place bya cross-wire n, pass- 5 ingoutsidevthe same and supported in lugs n pro ecting from the ends of thecasting.

Having described my invention and the with which I am 1. Thecombination, with the harness-levers,

and is formed with recesses, which are entered" i best manner ofreducing the same to practice movement at the rear ends thereof than atthe forward ends thereof, and pattern-controlling devices fordetermining the engagement of the hooks or jacks with the lifters ordraw-bars, substantially as described.

2. The combinatiomwiththeharness-levers, each having studs h h, and theupper and lower hooks or jacks having loose or sliding connection withthe studs, of the lifters or draw-bars, the returning-bars moving withthe lifters or draw-bars, the rock-shaft having arms 0" r at oppositeends thereof, the rods connecting the lifters or draw-bars with the saidarms, the said rods at one side of the dobby being connectedwith thesaid arms at points which are proportionately farther from the axis ofthe shaft than are the points of connection at the other side and thosepertaining to the upper lifter or draw-bar being connected with theupper arms at points which are proportionately farther from the saidaxis than are the points of connection between the lower lifter ordraw-bar and the lower arms, the inclined back-stop bar, andpattern-controlling devices determining the engagement of the hooks withthe lifters or draw-bars, substantially as described.

3. The combination, with the inclined backstop barf, the harness-levers,the studs 72. h thereon, and the hooks or jacks i 2", having loose orsliding connection with said studs, of the an gularlyplaced cross-wirest i", acting to determine the position of the hooks or jacks, thelifters or draw-bars, and means for operating the said lifters ordraw-bars with a greater range of movement at the rear ends thereof thanat the forward ends thereof, substantially as described.

In testimony whereof I affix my signature in presence of two witnesses.

GEO. W. STAFFORD.

Witnesses:

CHAS. F. RANDALL, WM. A. MACLEOD.

